A Word, Please: You may use ‘can’ without permission

An old schoolhouse in historic old San Simeon Village frames some of the 83,000–acre Hearst Ranch.
An old schoolhouse in historic old San Simeon Village frames some of the 83,000–acre Hearst Ranch, the vast property that has been in the Hearst family since the 1860s. In the 1800s, writes grammar expert June Casagrande, a teacher wouldn’t have flinched if a student used the word “may” instead of “can.”
(Spencer Weiner / Los Angeles Times)

It’s the late 1800s. A child in a one-room schoolhouse raises his hand. “Teacher, can I go to the outhouse?” “Of course you can,” the teacher replies.

Fast forward 100 years. A child sitting in a classroom raises his hand. “Teacher, can I go to the bathroom?” The teacher’s face twists into a mocking smirk. “I don’t know — can you?” The other children giggle. The boy revises his request: “May I go to the bathroom?” The teacher is triumphant. “Yes, you may.”

In the 1800s, using the word “can” to ask for permission was considered standard English. But in the century that followed, something happened. Grammar fussbudgets got it in their heads that “can” should refer to ability and “may” should refer to permission. So if you ask whether you can go to the bathroom, you’re not asking to be excused but instead asking about the state of your own digestive health.

Where did they get this idea? No one knows. But it could have to do with the fact that “may” was being used for permission centuries before “can” existed in our language. And if you go back far enough, you unearth a rather delicious irony: In the eighth century, “may” referred to ability — just as “can” does today. Theoretically, you could have said, “I’m so powerful that I may lift this boulder over my head.” Around the same time, “may” adopted a second meaning, possibility, which is still in use today: It may rain tomorrow. This is also when “may” started to refer to permission: May I please be excused?

June Casagrande speaks to a fellow grammar aficionado who shares her expertise as a “Roving Grammarian.”

About 200 years later, “can” showed up in the language. At that time, “can” didn’t refer to ability, exactly. It meant to know something or to know how to do something. So you could have said “I can do math,” but you couldn’t say “I can lift this boulder,” since boulder-hoisting doesn’t require know-how.

It took a few more centuries before “can” came to mean “to be able to do something” — at a time when “may” was already doing that job. And by the year 1500, “can” and “may” had overlapping meanings.

So for hundreds of years, “can” and “may” both meant to be able to do something or that something was possible. During that time, “may” also meant to have permission, while “can” did not. That changed around 1800 when “can” started being used to refer to permission, making “Can I go to the bathroom?” proper speech.

Then, in the 1900s, came the pushback.

“It didn’t take too long for teachers and grammarians of the day to proscribe that ‘can’ should only be used of ability and ‘may’ of permission,” writes Merriam-Webster’s Collegiate Dictionary, citing as an example the 1926 book “How to Say It: Helpful Hints on English,” by Charles Lurie. “There is no particular reason for the rule, except for the fact that ‘may’ has been used longer to mean ‘to give permission’ than ‘can’ has.”

In other words, it’s not true that you can’t say, “Can I go to the bathroom?” It’s just another example of a rule that bossy grammar scolds decided to impose on the rest of us.

Even so, sometimes you may want to accommodate the grammar scolds.

“‘May’ is the more formal word, and if you are at all concerned about being tut-tutted, a safe choice,” Merriam’s advises. “You may use ‘can’ if you wish, and you can use ‘may’ if it makes you feel better.”

June Casagrande is the author of “The Joy of Syntax: A Simple Guide to All the Grammar You Know You Should Know.” She can be reached at

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